]> git.madduck.net Git - code/myrepos.git/blobdiff - mr

madduck's git repository

Every one of the projects in this repository is available at the canonical URL git://git.madduck.net/madduck/pub/<projectpath> — see each project's metadata for the exact URL.

All patches and comments are welcome. Please squash your changes to logical commits before using git-format-patch and git-send-email to patches@git.madduck.net. If you'd read over the Git project's submission guidelines and adhered to them, I'd be especially grateful.

SSH access, as well as push access can be individually arranged.

If you use my repositories frequently, consider adding the following snippet to ~/.gitconfig and using the third clone URL listed for each project:

[url "git://git.madduck.net/madduck/"]
  insteadOf = madduck:

* Output list of failed repos to stderr when -s is used.
[code/myrepos.git] / mr
diff --git a/mr b/mr
index 0f80fc8c25165bec270fbbf9103ba8b67f960d60..95a7fe86a77535968990064cdad62c573a1a3227 100755 (executable)
--- a/mr
+++ b/mr
@@ -1,5 +1,7 @@
 #!/usr/bin/perl
 
+#man{{{
+
 =head1 NAME
 
 mr - a Multiple Repository management tool
@@ -12,18 +14,114 @@ B<mr> [options] update
 
 B<mr> [options] status
 
-B<mr> [options] commit -m "message"
+B<mr> [options] commit [-m "message"]
+
+B<mr> [options] diff
+
+B<mr> [options] log
+
+B<mr> [options] register [repository]
+
+B<mr> [options] config section [parameter=[value] ...]
 
 B<mr> [options] action [params ...]
 
 =head1 DESCRIPTION
 
-B<mr> is a Multiple Repository management tool. It allows you to register a
-set of repositories in a .mrconfig file, and then checkout, update, or
-perform other actions on all of the repositories at once.
+B<mr> is a Multiple Repository management tool. It
+can checkout, update, or perform other actions on
+a set of repositories as if they were one combined respository. It
+supports any combination of subversion, git, cvs, and bzr repositories, 
+and support for other revision control systems can easily be added.
+
+B<mr> cds into and operates on all registered repositories at or below your
+working directory. Or, if you are in a subdirectory of a repository that
+contains no other registered repositories, it will stay in that directory,
+and work on only that repository,
+
+These predefined commands should be fairly familiar to users of any revision
+control system:
+
+=over 4
+
+=item checkout (or co)
+
+Checks out any repositories that are not already checked out.
+
+=item update
+
+Updates each repository from its configured remote repository.
+
+If a repository isn't checked out yet, it will first check it out.
+
+=item status
+
+Displays a status report for each repository, showing what
+uncommitted changes are present in the repository.
+
+=item commit (or ci)
+
+Commits changes to each repository. (By default, changes are pushed to the
+remote repository too, when using distributed systems like git.)
+
+The optional -m parameter allows specifying a commit message.
+
+=item diff
+
+Show a diff of uncommitted changes.
+
+=item log
+
+Show the commit log.
+
+=back
+
+These commands are also available:
+
+=over 4
+
+=item list (or ls)
+
+List the repositories that mr will act on.
+
+=item register
+
+Register an existing repository in the mrconfig file. By default, the
+repository in the current directory is registered, or you can specify a
+directory to register.
+
+By default it registers it to the ~/.mrconfig file. To make it write to a
+different file, use the -c option.
+
+=item config
 
-Any mix of revision control systems can be used with B<mr>, and you can
-define arbitrary actions like "update", "checkout", or "commit".
+Adds, modifies, removes, or prints a value from the mrconfig file. The next
+parameter is the name of the section the value is in. To add or modify
+values, use one or more instances of "parameter=value". Use "parameter=" to
+remove a parameter. Use just "parameter" to get the value of a parameter.
+
+For example, to add (or edit) a repository in src/foo:
+
+  mr config src/foo checkout="svn co svn://example.com/foo/trunk foo"
+
+To show the command that mr uses to update the repository in src/foo:
+
+  mr config src/foo update
+
+=item help
+
+Displays this help.
+
+=back
+
+Actions can be abbreviated to any unambiguous subsctring, so
+"mr st" is equivilant to "mr status", and "mr up" is equivilant to "mr
+update"
+
+Additional parameters can be passed to most commands, and are passed on
+unchanged to the underlying revision control system. This is mostly useful
+if the repositories mr will act on all use the same revision control
+system.
 
 =head1 OPTIONS
 
@@ -32,56 +130,108 @@ define arbitrary actions like "update", "checkout", or "commit".
 =item -d directory
 
 Specifies the topmost directory that B<mr> should work in. The default is
-the current working directory. B<mr> will operate on all registered
-repositories at or under the directory.
+the current working directory.
 
 =item -c mrconfig
 
-Use the specified mrconfig file, instead of looking for on in your home
+Use the specified mrconfig file, instead of looking for one in your home
 directory.
 
 =item -v
 
 Be verbose.
 
+=item -s
+
+Expand the statistics line displayed at the end to include information
+about exactly which repositories failed and were skipped, if any.
+
 =back
 
 =head1 FILES
 
-B<mr> is configured by .mrconfig files. It searches for .mrconfig files in
-your home directory, and in the root directory of each repository specified
-in a .mrconfig file. So you could have a ~/.mrconfig that registers a
-repository ~/src, that itself contains a ~/src/.mrconfig file, that in turn
-registers several additional repositories.
+B<mr> is configured by .mrconfig files. It starts by reading the .mrconfig
+file in your home directory, and this can in turn chain load .mrconfig files
+from repositories.
+
+Here is an example .mrconfig file:
+
+  [src]
+  checkout = svn co svn://svn.example.com/src/trunk src
+  chain = true
+
+  [src/linux-2.6]
+  checkout = git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git &&
+       cd linux-2.6 &&
+       git checkout -b mybranch origin/master
 
 The .mrconfig file uses a variant of the INI file format. Lines starting with
-"#" are comments. Lines ending with "\" are continued on to the next line.
-Sections specify where each repository is located, relative to the
-directory that contains the .mrconfig file.
+"#" are comments. Values can be continued to the following line by
+indenting the line with whitespace.
+
+The "DEFAULT" section allows setting default values for the sections that
+come after it.
+
+The "ALIAS" section allows adding aliases for actions. Each parameter
+is an alias, and its value is the action to use.
+
+All other sections add repositories. The section header specifies the
+directory where the repository is located. This is relative to the directory
+that contains the mrconfig file, but you can also choose to use absolute
+paths.
 
 Within a section, each parameter defines a shell command to run to handle a
-given action. Note that these shell commands are run in a "set -e" shell
-environment, and B<mr> cds into the repository directory before running
-them, except for the "checkout" command, which is run in the parent of the
-repository directory, since the repository isn't checked out yet.
+given action. mr contains default handlers for the "update", "status", and
+"commit" actions, so normally you only need to specify what to do for
+"checkout".
 
-There are two special parameters. If the "skip" parameter is set and
-its command returns nonzero, then B<mr> will skip acting on that repository.
+Note that these shell commands are run in a "set -e" shell
+environment, where any additional parameters you pass are available in
+"$@". The "checkout" command is run in the parent of the repository
+directory, since the repository isn't checked out yet. All other commands
+are run inside the repository, though not necessarily at the top of it.
+The "MR_REPO" environment variable is set to the path to the top of the
+repository, and "MR_CONFIG" is set to the topmost .mrconfig file used.
 
-The "default" section allows setting up default handlers for each action,
-and is overridden by the contents of other sections. mr contains default
-handlers for the "update", "status", and "commit" actions, so normally
-you only need to specify what to do for "checkout".
+A few parameters have special meanings:
 
-For example:
+=over 4
 
-  [src]
-  checkout = svn co svn://svn.example.com/src/trunk src
+=item skip
 
-  [src/linux-2.6]
-  # only check this out on kodama
-  skip = test $(hostname) != kodama
-  checkout = git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
+If the "skip" parameter is set and its command returns nonzero, then B<mr>
+will skip acting on that repository. The command is passed the action
+name in $1.
+
+Here are two examples. The first skips the repo unless
+mr is run by joey. The second uses the hours_since function
+(included in mr's built-in library) to skip updating the repo unless it's
+been at least 12 hours since the last update.
+
+  skip = test $(whoami) != joey
+  skip = [ "$1" = update ] && [ $(hours_since "$1") -lt 12 ]
+
+=item chain
+
+If the "chain" parameter is set and its command returns nonzero, then B<mr>
+will try to load a .mrconfig file from the root of the repository. (You
+should avoid chaining from repositories with untrusted committers.)
+
+=item deleted
+
+If the "deleted" parameter is set and its command returns nonzero, then
+B<mr> will treat the repository as deleted. It won't ever actually delete
+the repository, but it will warn if it sees the repository's directory.
+This is useful when one mrconfig file is shared amoung multiple machines,
+to keep track of and remember to delete old repositories.
+
+=item lib
+
+The "lib" parameter can specify some shell code that will be run before each
+command, this can be a useful way to define shell functions for other commands
+to use.
+
+=back
 
 =head1 AUTHOR
 
@@ -93,97 +243,279 @@ http://kitenet.net/~joey/code/mr/
 
 =cut
 
+#}}}
+
 use warnings;
 use strict;
 use Getopt::Long;
 use Cwd qw(getcwd abs_path);
 
+$SIG{INT}=sub {
+       print STDERR "mr: interrupted\n";
+       exit 2;
+};
+
+$ENV{MR_CONFIG}="$ENV{HOME}/.mrconfig";
 my $directory=getcwd();
-my $config="$ENV{HOME}/.mrconfig";
 my $verbose=0;
+my $stats=0;
 my %config;
+my %knownactions;
+my %alias;
 
 Getopt::Long::Configure("no_permute");
 my $result=GetOptions(
-       "d=s" => sub { $directory=abs_path($_[1]) },
-       "c=s" => \$config,
-       "v" => \$verbose,
+       "d|directory=s" => sub { $directory=abs_path($_[1]) },
+       "c|config=s" => sub { $ENV{MR_CONFIG}=abs_path($_[1]) },
+       "v|verbose" => \$verbose,
+       "s|stats" => \$stats,
 );
 if (! $result || @ARGV < 1) {
-       die("Usage: mr [-d directory] action [params ...]\n");
+       die("Usage: mr [-d directory] action [params ...]\n".
+           "(Use mr help for man page.)\n");
+
 }
-my $action=shift @ARGV;
 
 loadconfig(\*DATA);
-loadconfig($config);
+loadconfig($ENV{MR_CONFIG});
 #use Data::Dumper;
 #print Dumper(\%config);
 
-my (@failures, @successes, @skipped);
-my $first=1;
+eval {
+       use FindBin qw($Bin $Script);
+       $ENV{MR_PATH}=$Bin."/".$Script;
+};
+
+# alias expansion and command stemming
+my $action=shift @ARGV;
+if (exists $alias{$action}) {
+       $action=$alias{$action};
+}
+if (! exists $knownactions{$action}) {
+       my @matches = grep { /^\Q$action\E/ }
+               keys %knownactions, keys %alias;
+       if (@matches == 1) {
+               $action=$matches[0];
+       }
+       elsif (@matches == 0) {
+               die "mr: unknown action \"$action\" (known actions: ".
+                       join(", ", sort keys %knownactions).")\n";
+       }
+       else {
+               die "mr: ambiguous action \"$action\" (matches: ".
+                       join(", ", @matches).")\n";
+       }
+}
+
+if ($action eq 'help') {
+       exec($config{''}{DEFAULT}{$action}) || die "exec: $!";
+}
+elsif ($action eq 'config') {
+       if (@ARGV < 2) {
+               die "mr config: not enough parameters\n";
+       }
+       my $section=shift;
+       if ($section=~/^\//) {
+               # try to convert to a path relative to the config file
+               my ($dir)=$ENV{MR_CONFIG}=~/^(.*\/)[^\/]+$/;
+               if ($section=~/^\Q$dir\E(.*)/) {
+                       $section=$1;
+               }
+       }
+       my %changefields;
+       foreach (@ARGV) {
+               if (/^([^=]+)=(.*)$/) {
+                       $changefields{$1}=$2;
+               }
+               else {
+                       my $found=0;
+                       foreach my $topdir (sort keys %config) {
+                               if (exists $config{$topdir}{$section} &&
+                                   exists $config{$topdir}{$section}{$_}) {
+                                       print $config{$topdir}{$section}{$_}."\n";
+                                       $found=1;
+                               }
+                       }
+                       if (! $found) {
+                               die "mr $action: $section $_ not set\n";
+                       }
+               }
+       }
+       modifyconfig($ENV{MR_CONFIG}, $section, %changefields) if %changefields;
+       exit 0;
+}
+elsif ($action eq 'register') {
+       my $command="set -e; ".$config{''}{DEFAULT}{lib}."\n".
+               "my_action(){ $config{''}{DEFAULT}{$action}\n }; my_action ".
+               join(" ", map { s/\//\/\//g; s/"/\"/g; '"'.$_.'"' } @ARGV);
+       print STDERR "mr $action: running >>$command<<\n" if $verbose;
+       exec($command) || die "exec: $!";
+}
+
+# work out what repos to act on
+my @repos;
+my $nochdir=0;
 foreach my $topdir (sort keys %config) {
        foreach my $subdir (sort keys %{$config{$topdir}}) {
-               next if $subdir eq 'default';
-               
-               my $dir=$topdir.$subdir;
+               next if $subdir eq 'DEFAULT';
+               my $dir=($subdir =~/^\//) ? $subdir : $topdir.$subdir;
+               my $d=$directory;
+               $dir.="/" unless $dir=~/\/$/;
+               $d.="/" unless $d=~/\/$/;
+               next if $dir ne $directory && $dir !~ /^\Q$directory\E/;
+               push @repos, [$dir, $topdir, $subdir];
+       }
+}
+if (! @repos) {
+       # fallback to find a leaf repo
+       LEAF: foreach my $topdir (reverse sort keys %config) {
+               foreach my $subdir (reverse sort keys %{$config{$topdir}}) {
+                       next if $subdir eq 'DEFAULT';
+                       my $dir=($subdir =~/^\//) ? $subdir : $topdir.$subdir;
+                       my $d=$directory;
+                       $dir.="/" unless $dir=~/\/$/;
+                       $d.="/" unless $d=~/\/$/;
+                       if ($d=~/^\Q$dir\E/) {
+                               push @repos, [$dir, $topdir, $subdir];
+                               last LEAF;
+                       }
+               }
+       }
+       $nochdir=1;
+}
+
+my (@failed, @ok, @skipped);
+foreach my $repo (@repos) {
+       action($action, @$repo);
+}
+
+sub action { #{{{
+       my ($action, $dir, $topdir, $subdir) = @_;
+       
+       my $lib= exists $config{$topdir}{$subdir}{lib} ?
+                       $config{$topdir}{$subdir}{lib}."\n" : "";
 
-               if (defined $directory &&
-                   $dir !~ /^\Q$directory\E\//) {
-                       print "mr $action: $dir skipped per -d parameter ($directory)\n" if $verbose;
+       if (exists $config{$topdir}{$subdir}{deleted}) {
+               if (! -d $dir) {
+                       return;
+               }
+               else {
+                       my $test="set -e;".$lib.$config{$topdir}{$subdir}{deleted};
+                       print "mr $action: running deleted test >>$test<<\n" if $verbose;
+                       my $ret=system($test);
+                       if ($ret != 0) {
+                               if (($? & 127) == 2) {
+                                       print STDERR "mr $action: interrupted\n";
+                                       exit 2;
+                               }
+                               elsif ($? & 127) {
+                                       print STDERR "mr $action: deleted test received signal ".($? & 127)."\n";
+                               }
+                               if ($ret >> 8 == 0) {
+                                       print STDERR "mr error: $dir should be deleted yet still exists\n\n";
+                                       push @failed, $dir;
+                                       return;
+                               }
+                       }
+               }
+       }
+
+       if ($action eq 'checkout') {
+               if (-d $dir) {
+                       print "mr $action: $dir already exists, skipping checkout\n" if $verbose;
                        push @skipped, $dir;
-                       next;
+                       return;
                }
 
-               print "\n" unless $first;
-               $first=0;
+               $dir=~s/^(.*)\/[^\/]+\/?$/$1/;
 
-               if (exists $config{$topdir}{$subdir}{skip}) {
-                       my $ret=system($config{$topdir}{$subdir}{skip});
+               if (! -d $dir) {
+                       print "mr $action: creating parent directory $dir\n" if $verbose;
+                       my $ret=system("mkdir", "-p", $dir);
+               }
+       }
+       elsif ($action eq 'update') {
+               if (! -d $dir) {
+                       return action("checkout", $dir, $topdir, $subdir);
+               }
+       }
+       
+       $ENV{MR_REPO}=$dir;
+
+       if (exists $config{$topdir}{$subdir}{skip}) {
+               my $test="set -e;".$lib.
+                       "my_action(){ $config{$topdir}{$subdir}{skip}\n }; my_action '$action'";
+               print "mr $action: running skip test >>$test<<\n" if $verbose;
+               my $ret=system($test);
+               if ($ret != 0) {
+                       if (($? & 127) == 2) {
+                               print STDERR "mr $action: interrupted\n";
+                               exit 2;
+                       }
+                       elsif ($? & 127) {
+                               print STDERR "mr $action: skip test received signal ".($? & 127)."\n";
+                               exit 1;
+                       }
                        if ($ret >> 8 == 0) {
                                print "mr $action: $dir skipped per config file\n" if $verbose;
                                push @skipped, $dir;
-                               next;
+                               return;
                        }
                }
-
-               if ($action eq 'checkout') {
-                       if (-e $dir) {
-                               print "mr $action: $dir already exists, skipping checkout\n";
-                               push @skipped, $dir;
-                               next;
-                       }
-                       $dir=~s/^(.*)\/[^\/]+\/?$/$1/;
+       }
+       
+       if (! $nochdir && ! chdir($dir)) {
+               print STDERR "mr $action: failed to chdir to $dir: $!\n";
+               push @failed, $dir;
+       }
+       elsif (! exists $config{$topdir}{$subdir}{$action}) {
+               print STDERR "mr $action: no defined $action command for $topdir$subdir, skipping\n";
+               push @skipped, $dir;
+       }
+       else {
+               if (! $nochdir) {
+                       print "mr $action: $topdir$subdir\n";
                }
-               if (! chdir($dir)) {
-                       print STDERR "mr $action: failed to chdir to $dir: $!\n";
-                       push @skipped, $dir;
+               else {
+                       print "mr $action: $topdir$subdir (in subdir $directory)\n";
                }
-               elsif (! exists $config{$topdir}{$subdir}{$action}) {
-                       print STDERR "mr $action: no defined $action command for $topdir$subdir, skipping\n";
-                       push @skipped, $dir;
+               my $command="set -e; ".$lib.
+                       "my_action(){ $config{$topdir}{$subdir}{$action}\n }; my_action ".
+                       join(" ", map { s/\//\/\//g; s/"/\"/g; '"'.$_.'"' } @ARGV);
+               print STDERR "mr $action: running >>$command<<\n" if $verbose;
+               my $ret=system($command);
+               if ($ret != 0) {
+                       if (($? & 127) == 2) {
+                               print STDERR "mr $action: interrupted\n";
+                               exit 2;
+                       }
+                       elsif ($? & 127) {
+                               print STDERR "mr $action: received signal ".($? & 127)."\n";
+                       }
+                       print STDERR "mr $action: failed ($ret)\n" if $verbose;
+                       push @failed, $dir;
+                       if ($ret >> 8 != 0) {
+                               print STDERR "mr $action: command failed\n";
+                       }
+                       elsif ($ret != 0) {
+                               print STDERR "mr $action: command died ($ret)\n";
+                       }
                }
                else {
-                       print "mr $action: in $dir\n";
-                       my $command="set -e; my_action(){ $config{$topdir}{$subdir}{$action} ; }; my_action @ARGV";
-                       my $ret=system($command);
-                       if ($ret != 0) {
-                               print STDERR "mr $action: failed to run: $command\n" if $verbose;
-                               push @failures, $topdir.$subdir;
-                               if ($ret >> 8 != 0) {
-                                       print STDERR "mr $action: command failed\n";
-                               }
-                               elsif ($ret != 0) {
-                                       print STDERR "mr $action: command died ($ret)\n";
-                               }
-                       }
-                       else {
-                               push @successes, $dir;
+                       if ($action eq 'checkout' && ! -d $dir) {
+                               print STDERR "mr $action: $dir missing after checkout\n";;
+                               push @failed, $dir;
+                               return;
                        }
+
+                       push @ok, $dir;
                }
+
+               print "\n";
        }
-}
+} #}}}
 
-sub showstat {
+sub showstat { #{{{
        my $count=shift;
        my $singular=shift;
        my $plural=shift;
@@ -191,16 +523,33 @@ sub showstat {
                return "$count ".($count > 1 ? $plural : $singular);
        }
        return;
+} #}}}
+if (! @ok && ! @failed && ! @skipped) {
+       die "mr $action: no repositories found to work on\n";
 }
-print "\nmr $action: finished (".join("; ",
-       showstat($#successes+1, "success", "sucesses"),
-       showstat($#failures+1, "failure", "failures"),
+print "mr $action: finished (".join("; ",
+       showstat($#ok+1, "ok", "ok"),
+       showstat($#failed+1, "failed", "failed"),
        showstat($#skipped+1, "skipped", "skipped"),
 ).")\n";
-exit @failures ? 1 : 0;
+if ($stats) {
+       if (@skipped) {
+               print "mr $action: (skipped: ".join(" ", @skipped).")\n";
+       }
+       if (@failed) {
+               print STDERR "mr $action: (failed: ".join(" ", @failed).")\n";
+       }
+}
+if (@failed) {
+       exit 1;
+}
+elsif (! @ok && @skipped) {
+       exit 1;
+}
+exit 0;
 
 my %loaded;
-sub loadconfig {
+sub loadconfig { #{{{
        my $f=shift;
 
        my @toload;
@@ -208,103 +557,338 @@ sub loadconfig {
        my $in;
        my $dir;
        if (ref $f eq 'GLOB') {
-               $in=$f; 
                $dir="";
+               $in=$f; 
        }
        else {
-               # $f might be a symlink
+               if (! -e $f) {
+                       return;
+               }
+
                my $absf=abs_path($f);
                if ($loaded{$absf}) {
                        return;
                }
                $loaded{$absf}=1;
 
-               print "mr: loading config $f\n" if $verbose;
-               open($in, "<", $f) || die "mr: open $f: $!\n";
                ($dir)=$f=~/^(.*\/)[^\/]+$/;
+               if (! defined $dir) {
+                       $dir=".";
+               }
                $dir=abs_path($dir)."/";
 
                # copy in defaults from first parent
                my $parent=$dir;
-               while ($parent=~s/^(.*)\/[^\/]+\/?$/$1/) {
+               while ($parent=~s/^(.*\/)[^\/]+\/?$/$1/) {
+                       if ($parent eq '/') {
+                               $parent="";
+                       }
                        if (exists $config{$parent} &&
-                           exists $config{$parent}{default}) {
-                               $config{$dir}{default}={ %{$config{$parent}{default}} };
+                           exists $config{$parent}{DEFAULT}) {
+                               $config{$dir}{DEFAULT}={ %{$config{$parent}{DEFAULT}} };
                                last;
                        }
                }
+               
+               print "mr: loading config $f\n" if $verbose;
+               open($in, "<", $f) || die "mr: open $f: $!\n";
        }
+       my @lines=<$in>;
+       close $in;
 
        my $section;
-       while (<$in>) {
+       my $line=0;
+       while (@lines) {
+               $_=shift @lines;
+               $line++;
                chomp;
                next if /^\s*\#/ || /^\s*$/;
-               if (/^\s*\[([^\]]*)\]\s*$/) {
+               if (/^\[([^\]]*)\]\s*$/) {
                        $section=$1;
-                       if (length $dir && $section ne "default" &&
-                           -e $dir.$section."/.mrconfig") {
-                               push @toload, $dir.$section."/.mrconfig";
-                       }
                }
-               elsif (/^\s*(\w+)\s*=\s*(.*)/) {
+               elsif (/^(\w+)\s*=\s*(.*)/) {
                        my $parameter=$1;
                        my $value=$2;
 
-                       # continuation line
-                       while ($value=~/(.*)\\$/) {
-                               $value=$1.<$in>;
+                       # continued value
+                       while (@lines && $lines[0]=~/^\s(.+)/) {
+                               shift(@lines);
+                               $line++;
+                               $value.="\n$1";
                                chomp $value;
                        }
 
                        if (! defined $section) {
                                die "$f line $.: parameter ($parameter) not in section\n";
                        }
-                       if (! exists $config{$dir}{$section} &&
-                             exists $config{$dir}{default}) {
+                       if ($section ne 'ALIAS' &&
+                           ! exists $config{$dir}{$section} &&
+                           exists $config{$dir}{DEFAULT}) {
                                # copy in defaults
-                               $config{$dir}{$section}={ %{$config{$dir}{default}} };
+                               $config{$dir}{$section}={ %{$config{$dir}{DEFAULT}} };
+                       }
+                       if ($section eq 'ALIAS') {
+                               $alias{$parameter}=$value;
+                       }
+                       elsif ($parameter eq 'lib') {
+                               $config{$dir}{$section}{lib}.=$value."\n";
+                       }
+                       else {
+                               $config{$dir}{$section}{$parameter}=$value;
+                               $knownactions{$parameter}=1;
+                               if ($parameter eq 'chain' &&
+                                   length $dir && $section ne "DEFAULT" &&
+                                   -e $dir.$section."/.mrconfig") {
+                                       my $ret=system($value);
+                                       if ($ret != 0) {
+                                               if (($? & 127) == 2) {
+                                                       print STDERR "mr $action: chain test interrupted\n";
+                                                       exit 2;
+                                               }
+                                               elsif ($? & 127) {
+                                                       print STDERR "mr $action: chain test received signal ".($? & 127)."\n";
+                                               }
+                                       }
+                                       else {
+                                               push @toload, $dir.$section."/.mrconfig";
+                                       }
+                               }
                        }
-                       $config{$dir}{$section}{$parameter}=$value;
                }
                else {
-                               die "$f line $.: parse error\n";
+                       die "$f line $line: parse error\n";
                }
        }
-       close $in;
 
        foreach (@toload) {
                loadconfig($_);
        }
-}
+} #}}}
 
-__DATA__
-# Some useful actions that mr knows about by default.
+sub modifyconfig { #{{{
+       my $f=shift;
+       # the section to modify or add
+       my $targetsection=shift;
+       # fields to change in the section
+       # To remove a field, set its value to "".
+       my %changefields=@_;
+
+       my @lines;
+       my @out;
+
+       if (-e $f) {
+               open(my $in, "<", $f) || die "mr: open $f: $!\n";
+               @lines=<$in>;
+               close $in;
+       }
+
+       my $formatfield=sub {
+               my $field=shift;
+               my @value=split(/\n/, shift);
+
+               return "$field = ".shift(@value)."\n".
+                       join("", map { "\t$_\n" } @value);
+       };
+       my $addfields=sub {
+               my @blanks;
+               while ($out[$#out] =~ /^\s*$/) {
+                       unshift @blanks, pop @out;
+               }
+               foreach my $field (sort keys %changefields) {
+                       if (length $changefields{$field}) {
+                               push @out, "$field = $changefields{$field}\n";
+                               delete $changefields{$field};
+                       }
+               }
+               push @out, @blanks;
+       };
+
+       my $section;
+       while (@lines) {
+               $_=shift(@lines);
+
+               if (/^\s*\#/ || /^\s*$/) {
+                       push @out, $_;
+               }
+               elsif (/^\[([^\]]*)\]\s*$/) {
+                       if (defined $section && 
+                           $section eq $targetsection) {
+                               $addfields->();
+                       }
+
+                       $section=$1;
+
+                       push @out, $_;
+               }
+               elsif (/^(\w+)\s*=\s(.*)/) {
+                       my $parameter=$1;
+                       my $value=$2;
+
+                       # continued value
+                       while (@lines && $lines[0]=~/^\s(.+)/) {
+                               shift(@lines);
+                               $value.="\n$1";
+                               chomp $value;
+                       }
+
+                       if ($section eq $targetsection) {
+                               if (exists $changefields{$parameter}) {
+                                       if (length $changefields{$parameter}) {
+                                               $value=$changefields{$parameter};
+                                       }
+                                       delete $changefields{$parameter};
+                               }
+                       }
+
+                       push @out, $formatfield->($parameter, $value);
+               }
+       }
+
+       if (defined $section && 
+           $section eq $targetsection) {
+               $addfields->();
+       }
+       elsif (%changefields) {
+               push @out, "\n[$targetsection]\n";
+               foreach my $field (sort keys %changefields) {
+                       if (length $changefields{$field}) {
+                               push @out, $formatfield->($field, $changefields{$field});
+                       }
+               }
+       }
+
+       open(my $out, ">", $f) || die "mr: write $f: $!\n";
+       print $out @out;
+       close $out;     
+} #}}}
+
+# Finally, some useful actions that mr knows about by default.
 # These can be overridden in ~/.mrconfig.
-[default]
-update = \
-       if [ -d .svn ]; then \
-               svn update; \
-       elif [ -d .git ]; then \
-               git pull origin master; \
-       else \
-               echo "mr update: unknown RCS"; \
-               exit 1; \
+#DATA{{{
+__DATA__
+[ALIAS]
+co = checkout
+ci = commit
+ls = list
+
+[DEFAULT]
+lib =
+       error() {
+               echo "mr: $@" >&2
+               exit 1
+       }
+       hours_since() {
+               for dir in .git .svn .bzr CVS; do
+                       if [ -e "$MR_REPO/$dir" ]; then
+                               flagfile="$MR_REPO/$dir/.mr_last$1"
+                               break
+                       fi
+               done
+               if [ -z "$flagfile" ]; then
+                       error "cannot determine flag filename"
+               fi
+               perl -wle 'print -f shift() ? int((-M _) * 24) : 9999' "$flagfile"
+               touch "$flagfile"
+       }
+
+update =
+       if [ -d "$MR_REPO"/.svn ]; then
+               svn update "$@"
+       elif [ -d "$MR_REPO"/.git ]; then
+               git pull origin master "$@"
+       elif [ -d "$MR_REPO"/.bzr ]; then
+               bzr merge "$@"
+       elif [ -d "$MR_REPO"/CVS ]; then
+               cvs update "$@"
+       else
+               error "unknown repo type"
+       fi
+status =
+       if [ -d "$MR_REPO"/.svn ]; then
+               svn status "$@"
+       elif [ -d "$MR_REPO"/.git ]; then
+               git status "$@" || true
+       elif [ -d "$MR_REPO"/.bzr ]; then
+               bzr status "$@"
+       elif [ -d "$MR_REPO"/CVS ]; then
+               cvs status "$@"
+       else
+               error "unknown repo type"
+       fi
+commit =
+       if [ -d "$MR_REPO"/.svn ]; then
+               svn commit "$@"
+       elif [ -d "$MR_REPO"/.git ]; then
+               git commit -a "$@" && git push --all
+       elif [ -d "$MR_REPO"/.bzr ]; then
+               bzr commit "$@" && bzr push
+       elif [ -d "$MR_REPO"/CVS ]; then
+               cvs commit "$@"
+       else
+               error "unknown repo type"
+       fi
+diff =
+       if [ -d "$MR_REPO"/.svn ]; then
+               svn diff "$@"
+       elif [ -d "$MR_REPO"/.git ]; then
+               git diff "$@"
+       elif [ -d "$MR_REPO"/.bzr ]; then
+               bzr diff "$@"
+       elif [ -d "$MR_REPO"/CVS ]; then
+               cvs diff "$@"
+       else
+               error "unknown repo type"
+       fi
+log =
+       if [ -d "$MR_REPO"/.svn ]; then
+               svn log"$@"
+       elif [ -d "$MR_REPO"/.git ]; then
+               git log "$@"
+       elif [ -d "$MR_REPO"/.bzr ]; then
+               bzr log "$@"
+       elif [ -d "$MR_REPO"/CVS ]; then
+               cvs log "$@"
+       else
+               error "unknown repo type"
+       fi
+register =
+       if [ -n "$1" ]; then
+               cd "$1"
        fi
-status = \
-       if [ -d .svn ]; then \
-               svn status; \
-       elif [ -d .git ]; then \
-               git status || true; \
-       else \
-               echo "mr status: unknown RCS"; \
-               exit 1; \
+       basedir="$(basename $(pwd))"
+       if [ -d .svn ]; then
+               url=$(LANG=C svn info . | grep -i ^URL: | cut -d ' ' -f 2)
+               if [ -z "$url" ]; then
+                       error "cannot determine svn url"
+               fi
+               echo "Registering svn url: $url"
+               mr -c "$MR_CONFIG" config "$(pwd)" checkout="svn co $url $basedir"
+       elif [ -d .git ]; then
+               url=$(LANG=C git-config --get remote.origin.url)
+               if [ -z "$url" ]; then
+                       error "cannot determine git url"
+               fi
+               echo "Registering git url: $url"
+               mr -c "$MR_CONFIG" config "$(pwd)" checkout="git clone $url $basedir"
+       elif [ -d .bzr ]; then
+               url=$(cat .bzr/branch/parent)
+               if [ -z "$url" ]; then
+                       error "cannot determine bzr url"
+               fi
+               echo "Registering bzr url: $url"
+               mr -c "$MR_CONFIG" config "$(pwd)" checkout="bzr clone $url $basedir"
+       else
+               error "unable to register this repo type"
        fi
-commit = \
-       if [ -d .svn ]; then \
-               svn commit "$@"; \
-       elif [ -d .git ]; then \
-               git commit -a "$@"; \
-       else \
-               echo "mr commit: unknown RCS"; \
-               exit 1; \
+help =
+       if [ ! -e "$MR_PATH" ]; then
+               error "cannot find program path"
        fi
+       (pod2man -c mr "$MR_PATH" | man -l -) || error "pod2man or man failed"
+list = true
+config = 
+
+ed = echo "A horse is a horse, of course, of course.."
+T = echo "I pity the fool."
+right = echo "Not found."
+#}}}